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Guide to Choosing & Using Wood Framing Stud & Joist or Porch & Deck Board Screw & Nail Fasteners
- FRAMING FASTENERS, NAILS, SCREWS - Structural Fasteners, screws, nails, bolts, hidden fasteners used for wood frame construction, including deck & porch construction
- Choices of deck nails, screws, coated fasteners, and hidden fasteners for deck floor, railing, joist hanger, and other construction connectors
- Using drywall screws, roofing nails, hanger tabs, or other improper fasteners for wood framing
- What are the Key Forces that Hold Nails & Screws in Wood as Structural Connectors?
- New Wood Preservatives and Their Corrosion Effects on Deck Nails, Screws, Connectors & Fasteners
- Typical[7] Nail Schedule for Metal Framing Connectors - Joist Hangers
- Stainless Steel Nails & Screws for Decks in Salt-Exposed or Wet/Humid Climates; aluminum deck nails?
- Hidden Deck Fasteners for Deck Boards; Screws for Use with Deck Floors - Decking
- Deck Joist & Beam Sizing Tables & A Quick Rule of Thumb for Sizing Joists
- Examples of poor or improperly made structural connections that lead to collapse of Decks and Porches
- CONNECTORS, FASTENERS, TIES - separate article
- DECK FASTENER CHOICES - separate article
- DECK & PORCH CONSTRUCTION - home
- DECK CONSTRUCTION BEST PRACTICES - separate article
- DECK DESIGN & BUILD - article series home
- FRAMING CONNECTORS & JOIST HANGERS - separate article
- Questions & Answers about structural fasteners, nails, bolts, or hidden fasteners for wood framing of buildings, decks & porches
- References
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InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.
Choices of deck structural & flooring fasteners: types of construction screws, nails, bolts to use when building a deck, railing, or exterior stair. This article explains critical safe-construction details for decks and porches, including avoiding deck or porch collapse and unsafe deck stairs and railings.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
Guide to Selecting the Proper Deck & Porch Structural Fasteners, Screws, Nails, Lags, Bolts
The Right & The Wrong Fastener Nails & Screws Used for Joist Hangers, Framing Ties, Framing Connector Plates
Details about choosing the right structural connectors for decks and how they should be installed are at FRAMING CONNECTORS & JOIST HANGERS.
At FRAMING FASTENERS, NAILS, SCREWS, & HIDDEN we discuss choosing the proper nail, screw, or hidden fastener for fastening deck boards, railings, or joist hangers. Spans, sizes and spacings for deck joists and deck beams are discussed in detail at FRAMING TABLES, SPANS for DECKS and are shown
in Table 4-7 and Table 4-8. Basic building framing information is found at FRAMING SIZE & Spacing, Age, Types.
Also see Deck Framing Tables, Spans and Deck & Porch Connections: Ledger Boards.
And see Preservative-Treated Framing Lumber. See Rot-Resistant Deck Lumber & Flooring for a discussion of lumber and flooring alternatives to preservative-treated wood. Also see Preservative-Treated Framing Lumber.
Our photo, left, shows three fasteners we have found used with steel joist hangers. This photo shows the heads of each of these fasteners.
Because the new wood preservatives ACQ (alkaline copper quat) and copper azole contain significantly more copper than the older CCA-treated lumber, they are estimated to be two to four times more corrosive to metals and galvanized coatings than the CCA they are replacing.
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- Hot dipped galvanized nails: At bottom of our photo above and shown fully nailed at left is a 1.5" long hot-dipped galvanized nail made by Simpson, and discussed just below. This is a proper fastener to use with galvanized steel joist hangers.
Other specialty fasteners used for joist hangers, post connectors and similar connector plates and ties are provided by a variety of manufacturers including special power-tool operated fasteners used with special Paslode™ or Senco™ mailers.
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- Roofing nails used for Joist Hangers? No. Use of roofing nails as structural fasteners is unsafe and violates building codes.
Watch out: do not use a roofing nail for fastening framing connectors. The short length of galvanized roofing nails and their easy availability tempts some inexperienced framers to use them for structural fasteners.
Do not do this. This is an improper fastener that will fail and risks catastrophic deck collapse.
In fact the final hammer blows that seat a roofing nail onto a steel framing connector can weaken or even completely sever the connection between the nail head and the nail shank,leaving no structural connection at all!
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- Drywall screws: In the middle is a 1.5" drywall screw. These screws are tempting to use because they are available, easy to install, do not require drilling.
Watch out: drywall screws are not structural fasteners.
We have inspected decks constructed entirely using interior drywall screws for both decking and for structural connections and joist hangers.
Do not do this. This is an improper fastener that will fail and risks catastrophic deck collapse.
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Comparing Joist Hanger Nails, Drywell Screws, Joist Hanger Tabs, & Utility "Construction" Screws - which are acceptable?
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Stainless steel utility screws: At the top of our photo (red arrow at left) is a 1 1/4" stainless steel screw used by a contractor to secure joist hangers when building the deck shown at the top of DECK & PORCH CONSTRUCTION.
The orange arrow points to a drywall screw, and the green arrow to the proper nail for steel structural fasteners, a Simpson Strong-Tie N10 DHDG 1 1/2" hot dipped galvanized "joist hanger" nail.
Watch out:
Although the stainless steel screw (red arrow) screw is also made by a company that makes structural fasteners, a quick look at the company's specifications for this screw revealed that the manufacturer specifically advised that this screw was not a structural fastener and should not be used with steel framing connectors.
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What about those little "Tabs" on Joist Hangers - can I just nail those in and skip the joist hanger nails?
 Watch out: the short answer is "no".
The locating tab (red oval in our photo at left) is intended to temporarily hold the joist hanger in place (just hammer it in) while you reach down into your nail apron to grasp a handful of joist hanger nails.
The tab is not a structural fastener and cannot be relied-on for that purpose.
Notice that the Tamlyn joist hanger shown in our photo provides for two joist hanger nails that will be hammered into the sides of the sides of the joist (two from each side), and three that will be nailed into the header or rim joist or ledger board (three at each side).
Our green arrows remind us of where we should see nails in the installed joist hanger.
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Key Forces that Hold Nails & Screws in Wood as Structural Connectors
Nailing
Stainless steel, galvanized, as well as proprietary-coating surfaced construction screws for use with treated lumber are available and of course are fine if used as recommended. But not the two screws shown in this photo and removed from decks we inspected. In the deck we inspected and where these improper screws had been installed, the contractor agreed to remove the screws and to replace them using the proper fasteners instead.
Watch out when removing and replacing wood framing fasteners:
Even then we were not quite sure that the deck was safely framed. Why?
The hole left by removing the wrong screws amounts to a "pre-drilled" opening in the ledger board or beam to which the joist hangers were later nailed. The holding power of a nail (or screw) fastener, the force that keeps the structure safely together, involves:
Shear force - force across the diameter of the fastener. The shear force resistance of a nail or screw is a function of the thickness and composition of the screw material.
Withdrawal force - the force that keeps the fastener from pulling out of the wood.
Screw fasteners have improved withdrawal force resistance because their threads cut into the surrounding wood.
Nails depend on friction for their resistance to withdrawal force - the "tightness" with which the wood member presses against the sides of the nail. When we nail into a pre-existing hole in a structural member, this withdrawal force may be compromised, especially depending on the diameter of the hole but also depending on the wood species and its dryness as well as the smoothness of the shank of the nail itself.
At DECK COLLAPSE Case Study we describe a serious deck collapse that occurred when the deck ledger pulled away from the building. The deck ledger discussed in that study had been nailed to the rim joist through siding, using too-small common nails, missing bolt connectors or other proper ties. The ledger, and thus the whole deck was unable to resist withdrawal forces. The deck pulled away from the building and collapsed. Other mistakes exacerbated the failure and fall. People were injured.
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Position of the fastener also is significant in withdrawal force of both nails and screws. For the identical size, weight, and number of fasteners, a nail that is horizontal with respect to the components it is supporting has less withdrawal force imposed on it (in general) than one which is nailed upwards: nailing a board straight "up" to a ceiling joist or rafter imposes more withdrawal force on the nails than nailing a board horizontally onto studs in a structural wall.
Length of the fastener is also significant. The fastener must be long enough to penetrate the structural wood members deeply enough to provide sufficient resistance against withdrawal. (That's why roof shingle nailing specifications, presuming the installation is over 3/4" plywood, expect the tip of the roofing nail to protrude through the 3/4" decking - to be sure that we have at least 3/4" of wood around the full-diameter shank of the roofing nail.)
Toe-nailing is particularly effective at improving the withdrawal force of nails used in framing construction. The crossing of nails past one another when nailed from opposing sides of a joist or stud forms a stronger connection than the same number of nails would provide if all placed on the same angle but just in one side of the framing member.
Most treatment manufacturers recommend that fasteners and hardware in contact with the new treated wood be stainless-steel, heavily coated hot-dipped galvanized, or proprietary fasteners tested and approved by the manufacturer.
New Wood Preservatives and Their Corrosion Effects on Deck Nails, Screws, Connectors & Fasteners
Hot-Dipped Galvanized Nails for Treated Lumber Decking
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 These deck construction nails, such as the joist hanger nails shown in our photo above, have three times as much zinc coating as standard G60 connectors. Examples of G185 coatings include Simpson’s Z-Max or USP Connector’s Triple-Zinc. Best Practices Guide to Residential Construction explains:
When using lumber treated with ACQ or copper azole, use hot-dipped galvanized fasteners that meet ASTM A153 with a minimum of 2 ounces of zinc coating per square foot.
Some galvanized nails intended for deck construction are marketed as “doublehot-
dipped.”
Connectors, flashings, and other hardware in contact with treated wood should meet ASTM A653, Class G185 (1.85 ounces of zinc per square foot of metal surface). Galvanized fasteners may stain redwood and cedar, however. |
Typical[7] Nail Schedule for Metal Framing Connectors - Joist Hangers
| Nominal Wood Joist Size |
Nails into Abutting Header
(through the connector)
(10d 1 1/2" joist hanger nails) |
Nails into Joist
(through the connector)
(10d 1 1/2" joist hanger nails) |
| Single Joists |
| 2x4 |
4 |
2 |
| 2x6 |
6 |
4 |
| 2x8 |
8 |
6 |
| 2x10 |
10 |
6 |
| 2x12 |
10 |
6 |
| 2x14 |
10 |
6 |
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Typical[7] Nail Schedule for Metal Framing Connectors - Joist Hangers - Built-up Beams
| Nominal Wood Joist Size |
Nominal Thickness (as number of 2x's making up the header or beam) |
Nails into Abutting Header
(through the connector - sum of both sides)
(10d 1 1/2" joist hanger nails) |
Nails into Joist
(through the connector, sum of both sides)
(10d 1 1/2" joist hanger nails) |
| Built-up headers & beams: double, triple, quad or custom thickness, joist & truss hangers |
| 2x6 |
2 - 2x6's (3" thick) |
8 |
4 |
| 2x8 |
2 - 2x8's (3" thick) |
12 |
6 |
| 2x10 |
2 - 2x10's (3" thick) |
14 |
8 |
| 2x12 |
2 - 2x12's (3" thick) |
14 |
8 |
| 2x14 |
2 - 2x14's (3" thick) |
14 |
8 |
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| 4x8 |
4x8 (3-1/2" thick) |
12 |
6 |
| 4x10 |
4x10 (3-1/2" thick) |
14 |
8 |
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| 2x10 |
3 - 2x10's |
14 |
8 |
| 2x10 |
4 - 2x10's |
6 (review needed) |
4 (review needed) |
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Stainless Steel Nails & Screws for Decks in Salt-Exposed or Wet/Humid Climates
In very wet or humid climates, or in areas subject to salt-water spray or deicing salts, stainless steel is the best choice. Stainless steel is also recommended for tropical hardwoods, which tend to cause staining with coated nails. Both types 304 and 316 stainless steel have been tested for use with the new wood preservatives ACQ and copper azole. Type 304 is suitable for above- ground applications. Type 316 is recommended in areas subject to salt or salt water.
Watch out: Never use stainless steel in contact with galvanized
steel, as the galvanized coating will quickly corrode.
Where fasteners such as nails, bolts, or lags are in contact
with metal connectors, use the same metal for both components.
Proprietary Deck Screw or Nail Coatings
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Many decking screws sold in home centers have newer proprietary ceramic and epoxy coatings over an electro galvanized core.
Originally developed for use with CCA-treated lumber, many have now been tested and approved for use with ACQ and copper azole.
Our photo, left, shows two proprietary-coating coated structural screws used for decks; the right-hand most screw is hot-dip galvanized. This photo shows these 2 1/2" screws from the side view.
Grip-Rite Fas'ners® produces "PrimeGuard Ten" exterior screws that use a coating approved for exterior use with all types of treated lumber.
Prudential produces galvanized exterior deck screws such as the one shown at the right in our photo, above. These screws are warranted "for as long as you own your home" and are rated for use in untreated or CCA pressure treated wood in residential structures. |
If using one of these fastener types, make sure that it is recommended by the manufacturer for the specific type of decking being installed.
Aluminum Deck Nails
Best Practices Guide to Residential Construction continues:
Watch out: Do not use aluminum fasteners, connectors,
or flashings in contact with pressure-treated wood. The
copper-based waterborne preservatives will cause corrosion
and premature failure.
Also see Preservative-Treated Framing Lumber.
Hidden Deck Fasteners for Deck Boards
Over time, face-nailed deck fasteners may loosen, stain the
wood decking, or lead to splitting and water penetration.
Particularly with higher-end decking materials, such as
tropical hardwoods, more customers are opting for hidden
fastening systems (see Deck & Porch Products, Manufacturers).
Each system is proprietary, and some require proprietary
tools supplied by the fastener manufacturer. Some
suppliers of hardwood decking recommend a specific
fastener for their product and may sell the fasteners along
with the decking. There are two types of systems. One, such
as Deckmaster® (Grabber Construction Products), uses a
right-angle bracket that fastens to the tops of the joists and
screws into the underside of the decking. These are easiest
to install if the installer has access from below the deck.
The other type uses individual fasteners that fit between
adjacent decking planks and screw down into the top of the
joist. These typically attach to the edges of the decking planks
with clips or prongs.
A variation on this type called Eb-Ty
(Blue Heron Enterprises) fits into slots cut into the edges of
adjacent deck boards with a plate jointer (see Figure 4-5 below).
The biggest concern with hidden deck fasteners is
whether they are strong enough to resist the tendency of
deck boards to warp or twist. For that reason, they are best
used with premium decking products, which are dimensionally
stable. Tropical hardwoods and composite decking
are good candidates for hidden fasteners.
-- Adapted with permission from Best Practices Guide to Residential Construction.
Guide to Selecting the Proper Deck or Porch Floor Decking Fasteners
Whether using nails or screws, make sure to choose a product that is up to the task both structurally and aesthetically.
In general, screws are more expensive to buy and install, but often they make for a neater job with fewer callbacks
due to boards popping up. Construction adhesives specially formulated for treated wood may be used in conjunction
with nails or screws.
Nails for Use with Deck Floors - Decking
If the decking is to be nailed, use either spiral-,
twist-, or ring-shanked nails to resist pullout. When using pressure-treated wood, the fasteners should be either hot-
dipped galvanized, meeting ASTM A153, or stainless steel Type 304 or higher (see New Preservatives and Corrosion, above and see Preservative-Treated Framing Lumber).
Galvanized nails sometimes cause discoloration with redwood, cedar, and tropical hardwoods, so stainless steel
is a safer choice with these materials. Aluminum nails are also an option for redwood or cedar, but they should not
be used with pressure-treated wood.
The bigger the head, the better the hold-down power. At a minimum, use a casing nail, preferably a common. Some manufacturers sell special decking nails with a head size in between the two. For 5/4" decking use a 10d (3-inch) nail. For thicker decking use a 16d (3 1/2") nail.
Deck Joist & Beam Sizing Tables & A Quick Rule of Thumb for Sizing Joists
Spans, sizes and spacings for deck joists and deck beams are discussed in detail at FRAMING TABLES, SPANS for DECKS and are listed
in Table 4-7 and Table 4-8.
Decking Spans for deck flooring are shown in the Table 4-4 below.
Screws for Use with Deck Floors - Decking
Power-driven screws are more expensive and a
little slower to install, but they are the best choice since
they do a better job of holding down the decking and are
more easily removed for repairs. For treated wood, use
either hot-dipped galvanized screws that meet ASTM
A153, stainless-steel multipurpose screws, or specialty
decking screws with proprietary coatings tested and approved
for use with the new types of wood treatments.
Multipurpose screws have a thicker shank and courser
thread than drywall screws, giving them greater strength
and better holding power. Some specialized decking screws
also have cutting nubs under the head for self-countersinking
in wood.
Others have special concave “pancake” heads for
composite decking. The composite-decking screws leave a
crisp hole in the decking surface without the typical pucker
of excess material (mushrooming) around the screw head
(see Figure 4-4 below).
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In addition to Phillips-head screws, decking screws
come with square-drive and star-drive heads that allow
higher torque driving without stripping the head.
Also see DECK COLLAPSE Case Study (collapse of a new code-approved deck) and DECK FLASHING LEAKS, ROT Case Study for an example of an older deck with rot and collapse due to improper construction and missing building flashing.
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-- Adapted with permission from Best Practices Guide to Residential Construction.
Hidden Deck Screws
"Hidden" deck screws are structural fasteners for connecting decking that use proprietary screws or backer connectors that do not appear on the deck surface. See:
- FastenMaster, [Cortex® hidden fastening system] Tel: 1-800-518-3569, Email: info@fastenmaster.com, Website: fastenmaster.com
- Hohmann & Barnard, Inc, produces a huge range of structural ties and anchors, including for masonry repair and restoration, stone anchors, rebar positioners, [Wing Nut 2-Seal™ Tie, wing nut veneer anchor seals air barriers], Offices in 8 U.S. cities, including H&B New York
30 Rasons Court,
Hauppauge, NY 11788
(P) 631-234-0600,
(F) 631-234-0683,
Toll: 800-645-0616, Website: www.h-b.com
More Reading
A complete guide to building decks, porches, & exterior stairs can be found at Related Topics above. Key articles include:
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Also see DECK COLLAPSE Case Study (collapse of a new code-approved deck) and DECK FLASHING LEAKS, ROT Case Study for an example of an older deck with rot and collapse due to improper construction and missing building flashing.
Frequently Asked Questions (FAQs) about deck screws, nails, & fasteners
...
Ask a Question or Search InspectApedia
Questions & answers or comments about structural fasteners or connectors for decks & porches.
Ask a Question or Enter Search Terms in the InspectApedia search box just below.
Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.
- Steve Bliss's Building Advisor at buildingadvisor.com helps homeowners & contractors plan & complete successful building & remodeling projects: buying land, site work, building design, cost estimating, materials & components, & project management through complete construction. Email: info@buildingadvisor.com
Steven Bliss served as editorial director and co-publisher of The Journal of Light Construction for 16 years and previously as building technology editor for Progressive Builder and Solar Age magazines. He worked in the building trades as a carpenter and design/build contractor for more than ten years and holds a masters degree from the Harvard Graduate School of Education.
Excerpts from his recent book, Best Practices Guide to Residential Construction, Wiley (November 18, 2005) ISBN-10: 0471648361, ISBN-13: 978-0471648369, appear throughout this website, with permission and courtesy of Wiley & Sons. Best Practices Guide is available from the publisher, J. Wiley & Sons, and also at Amazon.com
- Best Practices Guide to Residential Construction, by Steven Bliss. John Wiley & Sons, 2006. ISBN-10: 0471648361, ISBN-13: 978-0471648369, Hardcover: 320 pages, available from Amazon.com and also Wiley.com. See our book review of this publication.
- Decks and Porches, the JLC Guide to, Best Practices for Outdoor Spaces, Steve Bliss (Editor), The Journal of Light Construction, Williston VT, 2010 ISBN 10: 1-928580-42-4, ISBN 13: 978-1-928580-42-3, available from Amazon.com
- Manual for the Inspection of Residential Wood Decks and Balconies, by Cheryl Anderson, Frank Woeste (Forest Products Society), & Joseph Loferski, October 2003, ISBN-13: 978-1892529343, $39.00 at Amazon.com or at the InspectAPediaBookstore
- [1] Eric Galow, Galow Homes, Lagrangeville, NY. Mr. Galow can be reached by email: ericgalow@gmail.com or by telephone: 914-474-6613. Mr. Galow specializes in residential construction including both new homes and repairs, renovations, and additions.
- [2] Mark Morsching, Everflashing, Tel: 800-550-1667, Email: everflashing@gmail.com. The Everflashing product comes in G-185 and Stainless Steel and is intended for use with treated lumber with copper in it. Everflashing produces a variety of specialty flashing products including flashings for use with decks at deck ledgers and deck perimeters.
- [3] Cleveland Steel Structural Fasteners, 26001 Richmond Rd., Bedford Heights, OH 44146,| Phone: 216.464.9400, Fax: 216.464.9404, E-mail: info@clevelandsteel.com, Website: http://clevelandsteel.thomasnet.com/category/construction-hardware-division?
- [4] Daytona Bolt & Nut, 815 N. Beach Street, P.O. Box 1391,
Daytona, FL 32114,
P: 386-255-0248,
F: 386-257-5985,
E-mail:Daytona@DaytonaBolt.com
- [5] Schuler Mfg. & Equip. Co. Inc.,
63724 Richland Road,
Griswold, Iowa 51535, Tel: (712) 774-2228 Website: http://www.schulermfg.net/
- [6] Simpson Strong Tie®, Tel:1-800-999-5099, Website: http://www.strongtie.com/
- [7] "Tamlyn Structural Lumber Connectors, Masonry / Concrete Products, Pest Control, [catalog & reference guide]", Tamlyn, 13623 Pike Road, Stafford, TX 77477,
USA Toll Free 800-334-1676,
Phone: 281-499-9604,
Fax: 281-499-8948, (photo, above left), Website: http://tamlyn.com/ [copy on file as /structure/Framing/Connectors Framing/Tamlyn_Structural_Connector_Cat.pdf]
- [8] Incom Distributor Supply, PO Box 868, Fort Wayne IN 46801, Tel: 260-748, 5469, Website: http://shop.incomsupply.com/shop/, "... a growing nationwide network of over 500 Commercial Industrial Distributors" Incom Inc, 73-5600 Kauhola St Ste C, Kailua Kona, HI 96740, Tel: (808) 329-1311
- [9] USP Structural Connectors®, Tel: 1-800-328-5934, Email: uspcustomerservice@mii.com, Website: http://www.uspconnectors.com/
- [10] Double Shear Joist hangers include a cut-out/stamping that provides distributed, and properly-angled 45-degree nailing positions (load points) in the joist hanger. The angles assure proper toe-nailing of the hanger nails. Double shear nailing hangers are a patented [since 1984] feature of Simpson Strong-Tie ZMAX galvanized joist hangers. Other companies such as Silva Timber Products (in the U.K.) produce similar double-shear joist and truss hanger products.
- [11] Silva Timber Products, Unit 4, Albright Road
Widnes,
Cheshire,
WA8 8FY,
Tel: 0151 495 3111,
Fax: 0151 495 2255,
Website: http://www.silvatimber.co.uk/, Email: enquiries@silvatimber.co.uk
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
 The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
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